An international team of astronomers have discovered three earthlike planets orbiting their own suns, all of which could be hospitable to life. They discovered this with the help of TripleSpec, a near-Infrared Triple Spectrograph at California's Mount Palomar Observatory.

The findings reveal that the three planets orbit within their host stars' "habitable zones" - the orbital distance in which liquid water could exist, and the sweet spot for determining whether life could be possible.

The host stars, KOI 463.01, KOI 812.03 and KOI 854.01, belong to the M dwarfs stars. M dwarf stars are cooler, smaller and dimmer compared to our sun.

KOI 463.01, KOI 812.03 and KOI 854.01 are located in areas of the sky between the constellations Cygnus and Lyra, in the range of a few hundred to a few thousand light years away.

"There is a fairly solid argument that the vast majority of planets in the universe, and quite possibly the earthlike habitable zone planets, are planets orbiting M dwarfs," said Jamie Lloyd, associate professor of astronomy at Cornell University, in a statement.

Cornell researchers developed a technique using TripleSpec to measure metallicities and temperatures of M dwarf stars. Using data from TripleSpec they found that three earthlike planets have somewhat size, mass and temperature that is found on earth.

"Seventy percent of the stars in the universe are these small stars, not like our sun," said Philip Muirhead, researcher at the California Institute of Technology, in a statement. "So if these planets are common around small stars, and small stars are common in the universe, then most life in the universe may in fact exist around these types of planets, and not around earthlike systems and sunlike stars."

"If we saw signatures of oxygen in these planets' atmospheres, that would be a major step toward identifying extraterrestrial life in the universe," he said.

California